Automatic exchange system.



W. HQ MATTHIES.

AUTOMATIC EXCHANGE SYSTEM.

ABPLIOATION FILED Hoy-.12. 1910.

I 996,500, Patented June 27, 191.1.

. fd 6, b,

7 H f2' b2 ing ably adjustable circuit controlling devices WILLIAM HUGO `MATTHIES, F

ANTWERP, BELGIUM, ASSIGNOR TO WESTERN ELEC- TRIG COMPANY, OF NEW YORK, N. Y., .A CORPORATION 10Ey ILLINOIS.

AUTMATIC EXCHAN GE SYSTEM.

ieeeaco, I'

specification of Letters Patent.

Patented June 27, 1911.

Application led November 12, 1910. v Serial No. 591,970.

To all 'whom it may come-m: y Be it lmown that I, IVILLIAMH. MAT- '1'H1ns, citizen of the United States, .residing at Antwerp, Belgium, have invented a cer tain vnew and useful Improvement in Automatic Exchange Systems, of which the following is a full, clear, concise, and exact description.

rlhe invention relates to a system for movand switching selectors or other variin automatic telephone exchanges, In such systems 1t 'is customary to advance the selectors in an exchange from a sending staf tion, for example a subscribers station, by alternately opening and closing, as desired, one side of the metallic circuit leading from the subscribers set to the exchange, thus causing a number' of pulsations to go over this side to a switching relay, which in turn effects the advance 'of a selector in connection with it at this time. The other side of the line which eventually serves to hold all apparatus necessary for'maintaining the connection between the subscriber and the exchange While the interruptions take place in the first side of the line, is Vas a rule used, after a selector has been operated, to switch this particular selector over to a subsequent 4selector. 'lhis is done by intermittently connecting this side of the line to or cutting it oil from earth and correspondingly cutting in or oli a relay contained in this line which causes the switching of the selector. Over these arrangements the objpect vof the 1nven- `tion is characterized in this tha t the selectors scriber to release the connection about to be established at any desired time, i. e. also during the operation of a selector by simply opening the other side, over `which merely the line relay is excited, when restoring thc receiver to its hool. 0n the other'hand. if

this said circuit contains both sides ot' themetallic circuit, it isv possible tous@ the f K current traversing the circuit 'permanently closedduring the operation of the selectors, also for the purpose of holding the line or calling relay of the subscriber.A A further great advantage of the new arrangement is that it does away with almost every disadvantage caused usually When opening and closing with speed the `switching circuit and veniences (for instance breakingdown of insulations, is ofgreat importance with respect to the safe operation of the system.

The drawing represents the scheme of 4tWo suitable embodiments of the invention, such portions of the complete telephone system, however, which are unnecessary for an understanding of my invention, being omitted, but it will be understood that my invent-ion disclosed herein may be used in connection with any suitable system as, for example, that shown and described in my copending application, Serial No. 590,650, tiled November 4, 1910, for telephone exchange system.

In the arrangement according to Figure l the circuit for advancing and switching thc selectors contains but the one line a, Whereas in the arrangement according to Fig. 2 it comprises both lines 'a and o. In both cases the subscribers set T besides the usual telephone set is further equipped with a. device NSalled subscriber sender or number switch, which is suitably placed into a by-box. The meaning of all other parts of the figures will result from the following:

The operation of the circuit shown in Fig. l is as follows: As soon as the subscriber T,

scriber, removes his receiver from the hook, the following current 1s cut 1n: Earthed bat- Vtery B1 over the Winding of l1ne relay LR,

tact springs f1 and f2 at the subscribers sender or number switch NS, side a of the line, winding of a relay AR, ground, back to battery. Relay AR cuts in over 'a local circuit a relay SRjWhich in turn indirectly causes the motion of the lineiinder LS, which is merelyi represented by the contact brushes 711, b2, Z13 and contacts 01, 02, e?. The line relayfLR, onthe'other hand, earths con,-

Which practically have led to great incon.

desirous of a connection With a second sub' side l) of the line, switchhoo'k of set T, conburning of contacts). This ,fact

rogo

tact cfotheline'findcicoriesponding to bruslr b3, over'its front contact. i As soon as the'brus'h of the moved line finder reaches the earthed contacto3 lof subscriber T, the

lline finder comes to a standstill, so that brushes b1 and b2 rest uponcontacts c1 and and' sit still when `brush b? ofone of thesek line xv4v-inders is the first to. arrive at the earthed contact c3 of the subscriber. The line-finder LS now being engaged with the line,V ot' the calling subscriber, the line a is thenfconnected over resistance w1 to the selector relay WR and switching relay UR by means-of brush-fl-possibly after some automatic operations which areono interest here'liave, taken place previously or in the n'loantime.` During these operations subscriber l has adjusted his sender or number switch NS'according to the numeral o'f the desiredsubscriber, the apparatus at the exchange being in noway mfiuenced by this procedure. The number switch, for instance, consists of a number of contact disks placed side by side A(thousands, hundreds, tens and unilsffdisks) which are separately adjusted to their corresponding digitsand are then released 'one after the other by means of a wound up clock-work.` lVhen returning to their normal position they successively close and open a contact .a 1000, z 100,@1 10 and e l respectively.

Before the release of the adjusted contact disks thc-contact springs f1, f2, f3, are thrown into another position in which they are helduntil .the last contact disk has reachedits normalposition andtherefore the springs arefsuit'ably moved by a part which is rcmovedfrom its normal position When the clock-Work is wound up, but which 1s returned to itsnormal when the clock-Work has run down. The contact springs f, f2, f3

are'so arranged that the earthed contact spring f3 already engages with the contact spring fl when thecontact spring f2 is still in contact with spring f1. Consequently the line relay` LR is not cut oit when throwing the vsprings, but this relay receives current over sirinfs 1 and f3 before s rin s 1 andof relaysUR andlWR, resistance w1, brush b1 of line finder LS, contact c1, line a, contact f4, resistance wz. to earth. This current excites'only the switching relay UR, Whereasthe selecting relay WR does not receive the necessary current for its excitement because of the resistance wz being cut in. The switchingr relay UR attracts its armature thus removing an earth connection consisting of its back contact and armature to line 2 and relays R 1000 to R 1. If the Sub-l scriber now sets the `clock-Work of his number switch running, at rst the contact 2 1000 is closed and opened several times in succession according to the adjustment of its contact disk. At every closing of the con-r tact the .resistance wz is bridged through a shuntto earth, the current flowing over line a thus being intensified.

contact disk ot/contact a' 100 is released. The

Y In consequence the selecting relay iVR alternately attracts itsy armature according to the closings of theA ico.

switching relay UR beinggconstantly eX- cited by the current above described during these switching operations, is now deprived of its current andthus ents ina current over its armature and back contact, this current exciting relay R 1000 by flowing from battery B4 over contact f5, which is closed when starting selector W 1000, then right-hand winding of relay R 1000, line-2, back contact and armature of relay UR to earth. Relay R 1000 attracts its armatures andshifts the connection over its right-hand front contact from front contact ot'v selecting relay WR. to the right-hand armature of relay R 100. On

the other hand: it closes the circuit of its. left-hand holding winding through its lefthand frontj contact, thus remaining excited even after earth line 2 has been cut off, whichv loccurs when closing contact f4 before starting the release of contact disk of contact z 100 and at the same/time again exciting switching relay UR by current flowing-from battery B2 over resistancewz.- Vhen returningthe disk of contact e 100 to its norf mal'position, the same'operations will happen as above described With'the difference, however, that `now the impulses caused by selectingv relay WR will energizethe electromagnet of selector- W 100,l thus Vadvancing this selector. After restoring of 'contact at the. proper stage tact springs y A vancing selectors W -the line relay7 ot' Fig. 2 .removed from its hook at subscribers stadisk of contact e 100, contact ft is again opened for a short interval, thereby energizing relay R 100 by means of relay UR, relay R 100 cutting oft selector W 100 from contact of selecting relaw lVR, connecting the latter to selector W 10 instead. Similar operations recur when restoring contact disks of contacts e 10 and e 1, thereby adlO and W l respectively. Tf the clock-work of the number switch or a part connected therewith returns to its norl'mal-position, contact f4 is opened definitely.l

At the same time contact springs f1, are restored to their for-mer position,

lines a and b are again connected, and this before the earth overcontact spring f3 is removed from line Consequently the line relay' LR, which meanwhile was bridged to lines ab in a manner of no account to the nature of the invention grounding line a) remains fore.l Relay LR does not gized before the subscriber restores his receiver to the hook at end of conversation. The switch KD is designed to be operated when efore or after the complete operation of system as herein disclosed it is desired to restore the relays R 1000, R 100, R l0 and R l to their normal (for instance by energized asbebecome denerused for establishing the connection may be restored to their normal and madeready y for a new connection in any desired manner.

The chief difference between circuit shown in Big. 1 and circuit shown in Fig. 2 is that the circuit for advancing and switching the selectors contains not only line a, but both lines a and. This arrangement renders it possible to use the permanent current iiowing over 'the circuit during the operation of the various selectors also as a holding current for the subscriber. of the'fact that this permanent current is intermittently cut olf when switching the selectors, whereas the line relay must necessarily' remain ,constantly excited, the arrangement shown in Fig. 1 will have to' undergo some changes which will be outlined in the following: i

The operationl of the circuit showmin is as follows:

`When the receiver is tion T, the 'line relay LR becomes ,ener-- gized by a current 'which Hows from battery B1 over winding of relay LR, line t), con- V switchhook of suband f2,

scriber T, contact f, line a, winding'of relay AR to earth. The relay AR causes the starting ot the line linder LS', which comes soon as its brush b3' arrives to astandstill as at the contact c3 which is denergized condition.' This switch K maybe and is preferablyI disk. Each time .select-ing relay WR. corresponding to contact e 1000 has returned In view grounded through line relay LR. vl/hen' winding up the clockwork serving to return the contact disks of number switch NS, the contact springs f1 and f2A are opened.' Inasmuch, however, as contact spring f1 makescontact with contact spring fs before this, line relay LR remains energized by a current flowing from battery B1 *over line4 b, contact springs f1,

f3, f, /"7 to earth. Now the contact spring j and simultaneously or shortly after the set of contact springs f, f7 and fare operated. This set of springs, similar to ebntact springs f1, f2 and f3, is so arranged as to separate springs f and f7 but after the springs f and f3 come into contact. Consequently the line relay LR remains energized, although earth has been removed from the subscribers set, by a current flowing from battery B1 over winding of line relay LR, line Zn, contact springs f1, f3, f, f8, resistance wz, contact spring f4, line a, resistance w1, windings of relays WR and UR and earth. This current also energizes switching relay UR, whereas the selecting relay WR does not receive the necessary current for its excitement owing being cut in. If now the contact disk of the number switch NS corresponding to Vcontact e 1000 is released and restored, contact z 1000'is alternately closed and opened according to the adjustment of its contact the contactit closed, the resistancel fw2 is bridged over, so that the c-urrent flowing in the last mentioned circuit is intensiiied each time and excites the After the contact disk to normal but before the contact disk corresponding to contact e 100 has ceased rotating, the contact springs f6, 7 and f8 and simultaneously or shortly after alsocontact spring f4 are intermittently operated, with the result ofl line relay LR again receiving currentI over contact springs f, f7 and 'earth .at subscribers set, whereas relay UR now loses its current. After ally this has taken place, contact springs 7'* and f6, j", fsar'e returned to their first mentioned position, and the disk of contact e 100 commences to rotate. vThe operationsnow taking place are the same as described aboveA and recur at the rotation of the disks belonging to contacts a 10 and a 1 respectively. Il" all disks have returned to their normal, all contact springs are'also returned 'to the normal position shown in the to resistance w2 figure. The line relay LR, which in the meantime is bridged across lines a and b. in a is now excited over ecomes denergized only when the receiver is returned to its hook at end of conversation. In all other respects the selecting devices of Fig. 2 are/the same as in Fig. l and are therefore not shown here.

manner not shown here,

contact springs f1, f2 and Both modifications show that the circuit containing the relays WR and UR besides the resistance '1112 at the subscribers set also contains at the exchange a resistance w1 which is cut in permanently in the line. This resist-ance serves the purpose of rendering the intensity of the current flowing thr'ou h the circuit as independent as possible trom the length of line a and lines a, b respectively, that is to say independent from the resistance increasing together with the distance bet-Ween subscribers set and exchange, vthus making it feasible that but one adjust-ment of the selecting relay WR is necessary for all subscribers lines connected to the exchange in question. With this respect an advantageous effect might also be produced by suitably proportionating the resistance wz.

Naturally the invention is not restricted to the modifications shown. For instance in the place of subscribers set T there might be an operators position of the exchange containingr the selecting arrangement or of another exchange, without offending against the nature pf the invention.

I claim:

1. In a telephone exchange system, the combination with variably adjustable circuit controlling devices, of a common controlling circuit therefor, a resistance in said circuit, and means whereby said devices are adjusted 1n response to resistance changes in said circuit and are switched by thel opening of said circuit.

2. In va telephone exchange system the combination with variably adjustable circuit controlling devices, of a common circuit for cntrolling such devices, a resistance in said circuit, a shunt adapted to be closed around said resistance, and two relays also in said circuit, one of which is operated each timel said shunt is closcd'to adjust the device associated with the circuit and the other relay denergized upon the opening of the circuit to switch the circuit from one device to the next device.

3. In a telephone exchange system, the

combination with variably adjustable circuit controlling devices, of a common controlling circuit therefor, a resistance in said circuit, a shunt adapted to be closed around said resistance, two relays in said circuit one operated upon the shunting of the resistance to adjust the associated device and the. other dencrgized upon the opening of the circuit to switch the circuit from the first associated device to the next clectromcchanism, a line relay associated with said circuit, and a source of current supplying said relays in said circuit and said line relay. j

4. In al telephone exchange system thc combination with vafriably adjustable. circuit controlling devices, of a common controlling .circuit therefor extending' from a subseribers other of said relays being denergized by the y opening of said circuit, said pair of relays 'being adapted to control said devices, a

source of current supplying said line relay and said controlling relays, and an equalizing resistance in said circuit'- at the exchange.

5. In a telephone exchange system the combination with a plurality ofvariably adjustable circuit controlling devices, of a com` mon controlling circuit therefor, a resistance 1n sald circuit, electromagnetic means 1n said circuit operatingin response to'resistance f changes therein to adjust said devices, a relay controlled over said circuit and associated with one of Said devices for shifting the control from said device to 4another of said devices, and means operated in the ad'- justment of the first said device to render said relay operative.

6. In a telephone exchange system the combination with a plurality of variably adjustable circuit controlling devices, of a common controlling circuit therefor, aree` sistance in said circuit, electromagnetic means in said circuit operatingin response to resistance changes therein to adjust said devices, a relay associated with one of said devices 'operatingin response to the opening of said circuit for shifting thecontrol from such device to another of said devices, and means operated in the adjustment of the first said device to render said relay operative.

7. In a telephone exchange system, the

combination with a telephone circuit, of a plurality of variably adjustable circuit controlling devices adapted to be brought one after another into association with said circuit. relays controlling said devices, said relays being responsive to resistance changes in saidcircuit to adjust said devices and responsive to the opening of the circuit to shift said circuit from association with one of said devices to another of said devices.

S. In a. telephone exchange system, the combination with a vtelephone circuit, of a plurality of variably .adjustable circuit controlling devices, and relays common to said devices controlling the adjustment of s aid devices in response to resistance changes in said circuit and controlling the'association of said devices one after another` with said circuit in response to the opening of said 9. In a telephone exchange system, the combination with variably adjustable. circuit controlling devices, of a circuit for controlling such devices and two relays also in said ciruittoneof which, is peti-gaby r sistance changes in saidcircuit to azjust the devices' one' next device'. l

Witnessesg-..

FRANCISA. Cox, Ewmm' 'MGNTCHYK- 

